I figured by now, someone would have posted a YouTube clip of just what you're talking about, aloha. But I searched high and low and came up mostly empty.
- I do recall seeing a clip on Britain's "Fifth Gear" tv show where the presenter, after driving the snot out of an OEM electric Smart car, raised the issue of getting stranded, and then loaded a generator into the hatchback, plugged it into the car, fired it up and drove off. But you can never tell if it's for real on TV.
- A member of the Ottawa EV club tried this with his electric pickup (more practical, since the noisy, stinky, hot generator is on the back of the truck, not in the passenger compartment. He tried driving with it running, but I seem to recall it kept tripping the breaker. Maybe a case of not adequately sized generator for the job.
- Your post caused me to hit the local classifieds looking for a 2kW generator.
I'd need at least that to try this on the ForkenSwift, since its charger consumes ~1200 Watts at its max charge rate.
Found 1 video for you. Not exactly what you're asking, but close. The generator is apparently running the e-motor directly in this clip. The batt pack isn't installed yet. Pretty ghetto.
Keep in mind though: most EV chargers only output a fraction as much power as the car consumes while driving. A simple way to look at it: I could easily drain the ForkenSwift's (half worn out) pack by driving it non-stop at about 30 mph for 45 minutes. But then it would take ~8 hours on the charger to bring it back to 100%.
So even if I had a generator powering the battery charger while driving, it would only extend my range a little bit. It wouldn't permit me to drive until its gas tank ran dry. It would extend stop & go driving proportionately more than non-stop driving though.